Supersonic aircraft



FIG. 1 is a perspective view of the ornamental design of a supersonic aircraft showing our new design;

FIG. 2 is a top plan view of the supersonic aircraft;

FIG. 3 us a right side elevation view of the supersonic aircraft, with the left side being a mirror image, and with the broken line showing for illustrative purposes only and forming no part of the claimed design;

FIG. 4 is a front elevation view of the supersonic aircraft; and,

FIG. 5 is a rear elevation view of the supersonic aircraft. 

The ornamental design for a supersonic aircraft, as shown. 